Approach to Chronic Kidney Disease Flashcards
Chronic kidney disease (CKD) is an abnormality of kidney __ or __, present for > __months.
Chronic kidney disease (CKD) is an abnormality of kidney structure or function, present for > 3 months.
GFR criteria for CKD
GFR <60 ml/min/1.73m^2
GFR is used to quantify kidney function because of 3 reasons
- it is a marker of excretory function
- it is correlated with widespread damage to the kidneys
- it is associated with progressive complications of kideny disease
Glomerular filtration rate (GFR) definition: Rate that fluid is filtered across the __ ___ __ into the __ __
Rate that fluid is filtered across the
glomerular basement membrane into the renal tubules
there are many equations to solve GFR, but all need to be relative to ___ ____ ___ due to the difference in kidney size
all must account to body surface area
the gold standard of measuring GFR is measuring ___ clearance, but it is impracticeal because:
instead, we estimate GFR using ____. We must take into acount the age, ___ and ___ of the patient.
the gold standard of measuring GFR is measuring INULIN clearance, but it is impracticeal because: YOU NEED A CONSTANT INULIN INFUSION, MULTIPLE BLOOD AND URINE SAMPLES, AND REGRESSION ANALYSIS
instead, we estimate GFR using CREATININE. We must take into acount the age, SEX and ETHNICITY of the patient.
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GFR equation more accurate in younger patients and those with higher BMI and lower levels of kidney fucntion
the CKD-EPI
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factors that increase plasma creatinine (5) and lead you to underestimate creatinine levels /gfr
- high muscle mass
- ingestion of cooked meat
- creatine supplements
- race, ethnicity– african americans
- reduction of gut creatininases.
factors tha reduce creatinine secretion
medicaations like trimethorpim, cimetiidine, fenofibrate.
factors that reduce plasma creatinine
small muscle mass
amputation
muscle wasting disease
dialysis
- these will all tend that you overestimate GFR
the rock:
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this athlete with no limbs:
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Usually, the definition of CKD is having a GFR <60 ml/min/1.73m2. what if the CFR is more than that?
CKD may present as >60 ml/min AND evidence of kidney damage either through abnormal urinalysis of imaging
things in urine sediment that might indicate kidney structure abnormalities
- proteinuria. albuminuria >30mg/day or ACR >3. Can also be non-albuminuria
- dysmorphic hematuria or RBC casts
- WBC casts
- granular casts or renal tubular epithelial cells
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urine electrolyte issues that might indicate CKD
urine electrolyte wasting